This invention relates generally to color formulation development, and more particularly, to determining a color formula for reproduction of a color standard.
Plastic manufacturers typically receive orders from customers for colored plastics in amounts ranging from 10,000 pounds to 100,000 pounds. A colored plastic typically requires a specific color formula that is usually composed of four to five pigments or dyes in specified concentrations. A prior art process 10 for large-scale production of a colored plastic is illustrated in FIG. 1.
Initially, at 12, a customer places an order for a certain amount of plastic having a specific color and provides the manufacturer with a sample of the color.
If the color is not one of the manufacturer's standard colors, the manufacturer develops a color formula at 14 and using laboratory-scale equipment processes a 1 pound to a 5 pound batch from which a color sample or plaque is made at 15. The plaque or color sample is then sent to the customer for approval.
At 16, if the customer approves the color sample, the color sample becomes a color standard. Then at 17, the manufacturer begins production on a production line using the developed color formula.
However, it has been observed that a color formula that produces one color on laboratory-scale equipment produces a slightly different color when produced on a production line. While the color change is usually small, it is often noticeable to the customer and requires correction.
Thus at 18, the manufacture modifies the color formula by adjusting the relative concentrations of pigments or dyes to better match the customer's approved color standard.
For example, if the colored plastic initially produced on the production line is a little less yellow compared to the color standard, then a color technician on the production line will add a little more yellow pigment to bring the color back on target. This color correction process results in increased labor costs and lost production capacity of the production line. In addition, running the production line before the colored plastic matches the color standard results in wasted or rejected material.